Die-casting involves injecting molten material into molds (or dies) under pressure. Soft metals, such as aluminum, zinc, copper, and alloys thereof, etc. are typically used in die-casting processes. The dies are usually of a hardened metal, such as hardened steel. A die normally includes two body portions that when butted together close the die to form a cavity within the die that receives the molten metal. The molten metal hardens forming a cast object having an exterior surface that has the shape of an inner surface of the cavity. Separating the two body portions opens the die, and the cast object is ejected.
Die-casting dies are usually expensive and time consuming to manufacture. Moreover, the cost for setting up the dies for the die-casting process is relatively high. For these reasons, die casting is often viewed as an unviable option for manufacturing cast parts, especially for small quantities and prototypes.
As the two body portions are butted together, they are aligned (or registered), e.g., using pins and bushings. That is, bushings in one of the portions receive pins protruding from the other portion for registering the two halves. Improper registration may result in an excessive parting line on the cast object corresponding to where the two body portions met that may require machining or that may produce an unacceptable part. The bushings and/or pins can become worn over time, due to repeatedly opening and closing the die, resulting in improper registration.
The two body portions are usually cooled during casting. This usually involves passing a coolant, such as water, oil, or the like, through a flow passage within each of the body portions. The flow passage typically connects cooling locations within each body portion in series. This means that the coolant heats up as it successively passes from one cooling location to another, which can result in improper cooling.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for alternative die-casting systems.